Next-generation (5G and beyond) systems will make use of Massive Multiple Input Multiple Output (MIMO) architecture and millimeter wave (mmWave) operations. One of the main challenges of Massive MIMO systems is power consumption. Another challenge arises in beamforming, because of the increased latency associated with beamforming using all antenna elements present in Massive MIMO systems.
Furthermore, solutions proposed for beam tracking in mmWave systems are non-blind and require pilot signals to be sent in order to acquire beam direction. Such beam tracking can be time consuming and rely on Tx scanning across the beam space and Rx feedback. Because of the time used, such beam tracking may not be helpful in high-speed vehicular applications.